1. Field of the Invention
This invention relates to height gauges, and more particularly to improvements in a mechanism for finely adjusting the movement of a slider used when the slider is vertically moved along supports.
2. Description of the Prior Art
To finely adjust the movement of a slider of a height gauge, heretofore, there has been commonly practiced that a feed box formed separately of the slider is vertically movably provided on a support for vertically movably supporting the slider, the rough adjustment is performed in such a manner that a control wheel for vertically moving the slider, is operated in a state where the slider and the feed box are integrated by means of a fine adjustment screw, or the slider is directly grasped to vertically move the slider at high speed, thereafter, the feed box is affixed to the support, and the fine adjustment screw is adjusted to effect a screw-feed under this condition, whereby the slider is vertically moved at low speed relative to the feed box, thus enabling to perform the fine adjustment.
Or, a guide support is formed separately of and in parallel to the support vertically movably supporting the slider, the rough adjustment is performed in such a manner that a control wheel for vertically moving the slider is operated or the slider is directly grasped to vertically move the slider at high speed, then, the slider is affixed to the guide support by means of a set-screw and the like, and thereafter, the guide support itself is vertically moved at low speed by means of the fine adjustment screw provided on a base, so that the fine adjustment can be performed.
However, the height gauge having the conventional fine adjustment mechanism, wherein the fine adjustment mechanism for finely adjusting the slider is provided entirely separately of a mechanism vertically moving the slider at high speed without utilizing it at all, presents such disadvantages that construction of the height gauge as a whole tends to be complicated and the number of parts constituting the height gauge is large. Moreover, in order to perform the fine adjustment after the slider is vertically moved at high speed by operating the control wheel and so forth, it is necessary for an operator to transfer one of his hands from the control wheel to a portion of the feed box, etc. other than the slider, e.g., the fine adjustment screw or the like provided on the feed box for the measuring operation, and hence, the height gauge of the type described has not been suitable for a quick measuring operation. Because of this, necessity has been voiced for a height gauge in which a fine adjustment is performed quickly after the rough adjustment, and particularly, there has been a very strong demand for such a performance with a high accuracy reading height gauge of a digital indication type, in which a photoelectric encoder or the like is adopted.